【摘要】 现场测试发现地铁车辆一系钢弹簧断裂失效与其运营中表现出的中高频动态特性有关。为研究地铁车辆一系钢弹簧的动态特性,对线路运行的车辆零部件进行动态行为测试,发现一系钢弹簧在中高频段的动态响应异常明显。通过建立一系内外圈钢弹簧的有限元模型,计算分析了钢弹簧在中高频段的固有模态特性、动刚度特性、弹簧动态应力分布特征和橡胶垫刚度对弹簧应力的影响。结果表明:安装状态下内外圈钢弹簧的一阶模态频率分别为58 Hz、52 Hz,其与调查线路钢轨主波长波磨的通过频率相近。在1～1000 Hz位移激励下,一系钢弹簧刚度大小存在频变特性,在钢弹簧固有频率附近发生突变。60 Hz位移激励条件下,钢弹簧出现共振现象时,动态响应最为明显;其动剪应力呈波浪形分布,内簧1.3圈内表面、外簧1.5圈内表面附近的动剪应力最大。钢弹簧动剪应力与橡胶垫刚度正相关,减小弹簧橡胶垫的刚度可降低弹簧动剪应力水平。更多还原

【Abstract】 The on-site tests shows that the fracture failure of the primary steel spring is related to the dynamic characteristics of its medium and high frequency in operation. In order to study the dynamic characteristics of primary steel springs of metro vehicles, the dynamic behavior of vehicle components running on the lines was tested. It is found that the dynamic response of primary steel springs is obvious under medium and high frequency excitation. By establishing the finite element model of inner and outer coil steel springs, the natural mode characteristics, the dynamic stiffness characteristics, the dynamic stress distribution characteristics of the springs and the influence of rubber pad stiffness on springs stress were calculated and analyzed. The results show that the first modal frequencies of inner and outer spring are 58 Hz and 52 Hz, respectively, which are similar to the excitation frequencies of rail corrugation of the line. Under the displacement excitation of 1～1000 Hz, the stiffness of primary steel springs shows frequency-dependent characteristics, and has a sudden change near the natural frequency of the steel springs. Under 60 Hz displacement excitation, the dynamic response of steel springs is the most obvious due to the occurring of the resonance; the dynamic shear stress is wavy, and the maximum dynamic shear stress occurs at 1.3 rings for the inner spring and 1.5 rings for outer spring. The dynamic shear stress of spring is positively correlated with the stiffness of rubber pad. A decrease of the stiffness of the spring rubber pad can reduce the spring dynamic shear stress level.更多还原